The present invention generally relates to microelectronic power regulation systems and components. More particularly, the invention relates to a serial bus control scheme suitable for providing communication between various portions of a microelectronic power regulation system.
Microelectronic power regulation systems generally include a power regulator configured to supply a desired, regulated power to a microelectronic device such as microprocessors, microcontrollers, memory devices, and the like. The system may also include capacitors located near and/or packaged with the microprocessor to supply additional charge during the operation of the microprocessor. Such power regulation systems are configured so that the power regulator (e.g., a switching regulator such as a Buck regulator) provides nominal operating power to the microprocessor and the capacitors supply charge to compensate for transient power demands that result from operation of the microelectronic device. Such transient power demands may occur, for example, when several transistors of the microprocessor switch in the same direction at approximately the same timexe2x80x94e.g., when a portion of the device is powered off to conserve power or a portion of the device is activated.
As the speed and integration of microprocessors increase, the use of power regulation systems that only employ decoupling capacitors to compensate for or regulate transient power demands becomes increasingly problematic. For example, the number and/or size of the capacitors required to account for transient events generally increases as the integration of the microprocessor increases. The capacitors take up a relatively large amount of space on the package and can be relatively expensive. In addition, as the speed and the performance of the microprocessor increases, the severity (e.g., the amplitude) of the transient power demands and the frequency of the events tend to increase. Further, the microelectronic devices often become more sensitive to degraded power waveforms, which result from transient events, as the integration and speed of the devices increase. Capacitors within typical power regulation systems may be unable to adequately regulate such sever transient power demands. If not regulated or filtered, transient power events may result in a power or ground xe2x80x9cspikexe2x80x9d or xe2x80x9cbouncexe2x80x9dxe2x80x94i.e., momentary voltage levels below or above the nominal operating voltage of the microelectronic device, which in turn induces bit errors in digital logic of the microelectronic device through degraded noise margin and supply-induced timing violations. Accordingly, improved apparatus for responding to transient events that result during operation of a microelectronic device are desired.
Furthermore, although typical Buck regulators are generally suitable for controlling power to some microprocessors, such regulators are not well suited to supply relatively high current (e.g., greater than about 30 amps) at relatively high speed (e.g., greater than about 100 kHz). One reason that Buck regulators have difficulty supplying high current at high speed to the microprocessor is that the regulator is configured to supply a single core operating voltage (Vcc) to the entire microprocessor. Supplying power from a single source and distributing the power to a limited number of locations of the microprocessor may be problematic in several regards. For example, various portions of the microprocessor may operate more efficiently at different amounts of powerxe2x80x94e.g. at different current and/or voltage levels. To compensate for the different power requirements, the microprocessor may require additional components and integration to step the power up or down as needed. Such additional components and integration may undesirably add to the cost and complexity of the microprocessor and systems including the microprocessor. Further, supplying all or most of the power from a single regulated power source requires a relatively large power regulator, which is generally inherently slow to respond to changes in power demands.
Another problem associated with supplying the same operating power to a limited number of locations of a microprocessor is that microprocessor wiring schemes configured to distribute the regulator power to the microprocessor are generally complex and include relatively long wiring sections to supply power to sections of the device located away from the input source of the power. The relatively long wiring sections may cause delay and undesirable signal degradation or loss of the transmitted power. Accordingly, improved methods and apparatus for providing power to a plurality of portions of a microelectronic device and to supply various amounts of power to a plurality of locations on the microprocessor are desired.
The present invention provides improved apparatus and techniques for transmitting signals between portions of a microelectronic power regulation system.
While the way in which the present invention addresses the disadvantages of the prior art will be discussed in greater detail below, in general, the present invention provides a power regulation system capable of detecting a transient event, communicating between portions of the power system, and responding to the sensed transient power event.
In accordance with one exemplary embodiment of the present invention, a power regulation system in accordance with the present invention includes one or more secondary or transient suppression regulators coupled to a microelectronic device and configured to respond to or account for high-frequency transient power demands and a controller coupled to at least one of the secondary regulators. In accordance with one embodiment of the invention, the controller is configured to periodically poll the secondary regulator and to write or send information to the secondary regulator based on the polled information.
In accordance with one embodiment of the invention, a secondary regulator includes a slave controller configured to receive information from a master controller and to send information to the master controller. In accordance with various aspects of this embodiment, a serial interface protocol is used to communicate between the master controller and the secondary regulator. In accordance with various aspects of this embodiment of the invention, the protocol supports one or more of the following modes: write, broadcast write, output enable, broadcast output enable, read status, broadcast read status, and read command. In accordance with a further aspect of this embodiment, each transmission from the controller includes address information, including a unique address for each secondary regulator or a broadcast address.
In accordance with further embodiments of the invention, a serial communication bus includes a pair of transmission lines: a serial clock line and a serial data line. The transmission lines couple one or more secondary regulators to a master controller.
In accordance with various embodiments of the invention, each transient suppression regulator is coupled to a portion of the microelectronic device, such that the plurality of regulators can supply relatively independent transient suppression to various portions of the microelectronic device.
In accordance with various additional embodiments of the invention, one or more of the secondary regulators include a programmable integrated circuit. In accordance with one or more aspects of this embodiment, the integrated circuit includes injector control, segmented current switch banks for sinking and/or sourcing current to the microelectronic device, a temperature monitor, a charge well monitor, programmable parameters, a serial interface for configuration, signal generators (e.g., to send signals to a controller) or any combination of these elements.
In accordance with another embodiment of the invention, a power regulation system includes a one or more primary regulators, one or more secondary regulators coupled to one or more primary regulators, and a controller coupled to one or more of the secondary regulators and optionally to one or more of the primary regulators. In accordance with one aspect of this embodiment, a system includes a plurality of primary regulators and each primary regulator is coupled to a different portion of a microelectronic device. In accordance with another aspect of this embodiment, two or more of the plurality of primary regulators are configured to provide different levels of power to the different portions of the microelectronic device. In accordance with yet a further aspect of this embodiment, the controller is configured to receive a signal indicative of a transient event and drive one or more of the primary regulator in response to the sensed transient event.